1. Field of the Invention
The present invention relates generally to the field of circuit characterization. More particularly, the present invention relates to the field of integrated circuit device characterization.
2. Description of Related Art
Integrated radio frequency (RF) circuit devices may be measured using network analyzers that typically operate from approximately 0.1 GigaHertz (GHz) to approximately 20 GHz. As the sensitivity of a typical network analyzer is limited to no less than several ohms of reactance, integrated circuit devices that are to operate at relatively low frequencies and/or with electrical characteristics having relatively low values may not be measured using network analyzers.
As one example, an integrated inductor that has an inductance below 100 nanoHenries (nH) and that is to operate at a frequency of approximately 3 MegaHertz (MHz) could not be measured by a typical network analyzer even if the network analyzer could be operated at a relatively lower frequency such as approximately 1 MHz, for example. As another example, inductors comprising a magnetic material such as a nickel iron (NiFe) permalloy, for example, cannot be measured by a typical network analyzer because such inductors can only be operated at relatively low frequencies below 100 MHz, for example. The magnetic material otherwise becomes lossy.
Characterizing an integrated RF circuit device such as an inductor, for example, at relatively high frequencies with a network analyzer is challenging. The cross-sectional area of the conductor for the inductor becomes reduced due to skin effects, thereby increasing the resistance of the inductor. Parasitic capacitances and resistances in the substrate of the integrated RF circuit device depend on the frequency at which the integrated RF circuit device operates. Also, parasitics exist in the cables and probes of the network analyzer.